Tips for eliminating ice pick highs

cragginshred

cragginshred

Fractal Fanatic
I am using either the Plexi 1 or a Marsha Be for medium gain tones and notice the higher solo notes have weird ice pick in the forehead overtones -for lack of better way to explain it. Highs, mids and bass pretty much at noon.
Running a FET before the amp and an eq to fatten up the tone. Tried a filter once with no luck (not quite sure how to set the parameters) help.
 
This was for me the greatest challenge in getting good sounds from medium- to high-gain presets in the Axe-Fx. Different firmware revisions have had the syndrome to different degrees, but it has pretty much always been there in the amp sims I use. There are several things you can change that will help you tame them. First, it appears to me that the undesirable overtones originate primarily in the power amp section of the amp block. Beyond the obvious steps of turning down treble and/or presence, some combination of the following changes has always worked for me, in rough order of preference:

1. Reduce MV and increase Drive.

2. Reduce Hi Freq Resonance.

3. Reduce the Hi Cut frequency.

4. Increase Sag.

5. Reduce Transformer Hi Freq.

6. Place a PEQ in front of the amp block, set filter 5 to Blocking, and turn down the frequency until the sound just cleans up.

You're walking a fine line here, so make small changes to one parameter at a time and listen carefully before going further. It's easy to get rid of the harshness at the expense of dulling the edge of your sound.

Also, work with the amp sim first (Drive block bypassed). Once you've got it cleaned up, kick in the Drive. If the harshness returns, tweak the tone controls of the Drive block to get rid of it.
 
This is something I struggle with too, especially on my Strat. I've noticed that the more articulate the pickups are on the high-end the more pronounced this issue is. I've got WCR SR's installed and it has a very clear, articulate high end that translates into the ice-pick highs on the AxeFX. So I've used a number of things to reduce that... some with success. Most of what Jay suggests above I have tried although his #1 isn't something I have played around with too much, so I'll definitely have to give that a go. I primarily use both the high-cut options as well as the PEQ before the amp trick and sag adjustment. Also check to see if the damp parm is too high, reducing that sometimes helps.

I've actually been considering auditioning some different pickups, but the WCRs sound so good when you get over that hump. :)
 
Jay Mitchell said:
6. Place a PEQ in front of the amp block, set filter 5 to Blocking, and turn down the frequency until the sound just cleans up.
Click to expand...

I've always placed the blocking PEQ after the CAB block to tame the harsh high freqs, but as you said the sound can quickly become dull if not careful. I've recently tried to move the blocking PEQ before the amp instead, and to me it sounds and feels better although the harshness becomes more audible. Would you generally recommend blocking before the amp and not after the cab?
 
torkolort said:
I've always placed the blocking PEQ after the CAB block to tame the harsh high freqs, but as you said the sound can quickly become dull if not careful. I've recently tried to move the blocking PEQ before the amp instead, and to me it sounds and feels better although the harshness becomes more audible.
Click to expand...
When you EQ after the amp block, you're attempting to remove problem overtones after the amp block has added them. When you EQ in front of the amp block, you are attempting to prevent (or reduce) the generation of the overtones in the first place. I find the latter approach (prevention) more effective. Keep in mind that the cutoff frequency of the blocking filter must be set to a lower value when used in front of the amp, since you want to reduce the level of the fundamentals that lead to generation of the unwanted overtones, rather than the overtones themselves.

Would you generally recommend blocking before the amp and not after the cab?
Click to expand...
It depends entirely on what you're trying to do. If you're looking to clean up distortion products - in any frequency range, not just highs - with EQ, it's usually more effective in front of the amp block. In the presets in which I use pre-EQ in this way, I place the PEQ at the very beginning of the signal chain. It then helps clean up the drive block as well as the amp block.

Note also that you may need to add some restorative gain to compensate for the frequencies you cut. Do a quick A/B with the block active and bypassed and set the level parameter to get the two to match.
 
Try applying a modifier to the tone on the fet set it to pitch and adjust the curve so that the higher the pitch, the tone will roll off. This works great for me.
 
mwc2112 said:
This is something I struggle with too, especially on my Strat. I've noticed that the more articulate the pickups are on the high-end the more pronounced this issue is.
Click to expand...

FWIW
I don't have issues with the EMG81 or the Alumitone, both are 'bright' buit pleasant, it's the SSl-1s that are shrill and, yes, in a Strat. ;)
 
Will try all, thanks! it is interesting when trying to cop the Lincoln Brewster tone at lower volumes with an FRFR set up it is easier, but ou tin the studio with 4x12 cabs it is the icepick scenario,... will try changes tonight!
 
The issue is there to some extent regardless of pickups, although brighter pickups tend to make it more evident. It is there with my Strat with late '60s vintage replica pickups, as well as with my Epi '56 Gold Top Les Paul with p90s. It is not a digital artifact; I have encountered very similar issues with physical amps. In the Axe-Fx, it takes careful tweaking to get rid of without dulling the sound.
 
cragginshred said:
at lower volumes with an FRFR set up it is easier, but ou tin the studio with 4x12 cabs it is the icepick scenario,...
Click to expand...
This would imply that the IR you use with the FRFR speaker is helping clean it up and that the physical cab is brighter as you are mic'ing it in the studio. You may find that mic'ing technique is the biggest culprit here.
 
Jay Mitchell said:
The issue is there to some extent regardless of pickups, although brighter pickups tend to make it more evident.
Click to expand...

Yes, and I should have elaborated that changing pickups would likely be more of a band-aid/masking-the-problem fix as opposed to addressing the real issue. But it's a band-aid that would (possibly) make it a lot easier to compensate in the AxeFX.
 
Jay Mitchell said:
When you EQ after the amp block, you're attempting to remove problem overtones after the amp block has added them. When you EQ in front of the amp block, you are attempting to prevent (or reduce) the generation of the overtones in the first place. I find the latter approach (prevention) more effective.
Click to expand...

That seems by far like the most reasonable approach, but does this also apply for the CAB block? When using IRs like V30 or Cali with an SM57, the highs tend to sound a very shrilling. I haven't had the time to experience enough with this so I'm wondering: Can we achieve the same / better result by blocking the highs before the AMP rather than after the CAB, or are the shrilling highs part of the characteristics of those IRs which can't be tamed at an earlier stage?
 
The UAD Pultec is one of the sweetest EQs I have. This PEQ setting very closely mimicks it's behaviour, when set to 16k Attenuation 5, which softens the high end somewhat.

download at:
http://forum.fractalaudio.com/share...-effects-emulations-thread-16.html#post507751

Pultec16kATT5.jpg
 
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DonPetersen said:
The UAD Pultec is one of the sweetest EQs I have. This PEQ setting very closely mimicks it's behaviour, when set to 16k Attenuation 5, which softens the high end somewhat.

http://forum.fractalaudio.com/share...-effects-emulations-thread-16.html#post507751
Click to expand...

Love that plugin too!!!!

Don, I am Ultra-less and in waiting for the II, does your EQ mimick the boost + cut feature of Pultec? I.e. a low shelf cut with a fairly wide Q low boost at the knee? That is my fav use of the Pultec.

Thanks,
Richard
 
torkolort said:
That seems by far like the most reasonable approach, but does this also apply for the CAB block?
Click to expand...
I'm not sure what your question is.

I haven't had the time to experience enough with this so I'm wondering: Can we achieve the same / better result by blocking the highs before the AMP rather than after the CAB,
Click to expand...
Asked and answered. If the excess highs are due to overtones being created by the amp block, pre-EQ is generally more effective at eliminating them while minimizing any change to the character of the amp sim.

Can we achieve the same / better result by blocking the highs before the AMP rather than after the CAB,
Click to expand...
See above.

are the shrilling highs part of the characteristics of those IRs which can't be tamed at an earlier stage?
Click to expand...
No. Unless you set the "Drive" parameter to a nonzero value the cab block is linear. It doesn't matter whether you place EQ before or after a linear block. It only matters with nonlinear blocks, e.g., amp, drive, compressor.
 
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